1. Field
The present invention relates to a pedal simulator, and more specifically, to a pedal simulator capable of increasing a sense of a pedal.
2. Description of the Related Art
In general, a brake system for braking is necessarily mounted in a vehicle. Recently, a system for electronically controlling braking hydraulic pressure transferred toward wheel cylinders mounted on wheels to obtain a more powerful and stable braking force has been proposed. As an example of the electronic brake system, an anti-lock brake system (ABS), a brake traction control system (BTCS), or an electronic stability control system (ESC), etc. has been proposed.
The electronic brake system provides a sense of the pedal by having a separate hydraulic pedal sensation simulating device (hereafter, referred as a pedal simulator) installed to provide a sense of the pedal for a driver at the time of braking. At this time, the pedal simulator, which is designed to provide reaction force similar to that of the pedal simulator of a conventional brake system (CBS), has been used.
In FIG. 1, a conventional pedal simulator is shown.
Referring to FIG. 1, the pedal simulator 10 provides a sense of the pedal by including: a simulator block 11 having a simulation chamber 12 which is connected with a master cylinder 1 and into which hydraulic pressure, generated according to the pedal pressure of a brake pedal 2, is introduced; two pistons 21 and 22 provided in the simulation chamber 12; and two springs 23 and 24 and two rubber dampers 25 and 26. Also, oil stored in the simulation chamber 12 is connected through a flow path 13 connected with a reservoir 3, so the oil pressurized according to movement of the pistons 21 and 22 is introduced into the reservoir 3. At this time, a simulation valve 30 is installed in the flow path 13 to control the flow of oil between the reservoir 3 and the simulation chamber 12. That is, the conventional pedal simulator 10 provides a sense of the pedal using the springs 23 and 24 and the rubber dampers 25 and 26.
However, since the pedal simulator 10 achieves a sense of the pedal only using the springs 23 and 24 and the rubber dampers 25 and 26, a difference between pedal pressure of the brake pedal 2 and the reaction force at the time of releasing of the pedal pressure is hardly generated, and thus there is a problem of providing a unfamiliar sense of braking for a driver.
Also, the plurality of springs 23 and 24 and the plurality of rubber dampers 25 and 26 are needed to provide a sense of the pedal, and also the simulation valve 30 should be separately provided, and thus there are problems of having a complicated configuration and increasing costs.
The pedal simulator according to an embodiment of the present invention is configured as a closed circuit between the simulation chamber and the accumulator, and can adjust pedal pressure of the brake pedal and a sense of the pedal at the time of releasing the pedal pressure by providing a sense of the pedal through the flow path resistance of the orifice.